Japanese Patent Application Laid-Open No. 2008-98379 (Patent Document 1) discloses a technique relating to a two-dimensional photonic crystal-surface emitting laser device (hereinafter referred to as a “photonic crystal laser”) as a semiconductor laser device and a manufacturing method thereof. The surface emitting laser device includes a substrate, a lower cladding layer provided on the substrate, an active layer provided on the lower cladding layer and emitting light by injection of carriers, and an upper cladding layer provided on the active layer. The two-dimensional photonic crystal has a structure in which voids having a depth reaching the lower cladding layer from the upper cladding layer through the active layer are periodically arranged along a main surface of the active layer.
Japanese Patent Application Laid-Open No. 2007-234727 (Patent Document 2) discloses a technique relating to a surface emitting laser device (semiconductor laser device). This surface emitting laser device includes a photonic crystal layer in which pores are two-dimensionally arranged on a plane orthogonal to a stacking direction on a substrate. A cladding layer having an oxidized region, which has been oxidized through the pores, and an unoxidized region is provided between the substrate and the photonic crystal layer. A refractive index of the oxidized region is lower than a refractive index of the photonic crystal layer. The photonic crystal layer and the unoxidized region of the cladding layer include Al, Ga, and As.